TWI501135B - LCD touch device - Google Patents

Description

LCD touch device

The present invention relates to a touch device, and more particularly to an LCD (liquid crystal display) touch device.

A general touch device superimposes a touch module on a screen. However, such a touch device has a large thickness and cannot meet the light and thin market demand, and its cost is also high.

In order to solve this problem, there is a design that integrates the screen and the same material layer of the touch module. However, the thickness that can be reduced by the touch device cannot meet the requirements of some high-end products.

It is also known to attempt to implement a touch function on a display. The general practice is to add additional electrodes to the display circuit layer to form a touch capacitor. However, such practices can reduce product yield and increase costs.

In order to solve the aforementioned problems, there is a need for a novel, low-thickness, and easy-to-produce touch device.

An object of the present invention is to provide an LCD touch device capable of providing a display function and/or a touch sensing function by applying a composite voltage source to an LCD structure.

Another object of the present invention is to disclose an LCD touch device, which can utilize one One of the upper surfaces of the LCD structure provides a touch plane.

Another object of the present invention is to disclose an LCD touch device that can provide a dual touch plane using two surfaces of an LCD structure.

Another object of the present invention is to disclose an LCD touch device capable of detecting a touch event by sensing an amplitude change, a phase change amount, or a frequency change amount of an AC voltage of a composite voltage source.

Another object of the present invention is to disclose an LCD touch device that provides four modes of operation by turning off/on a DC voltage component and/or an AC voltage component of a composite voltage source.

Another object of the present invention is to disclose an LCD touch device that simplifies the structure of the touch device to reduce product thickness, improve yield, and reduce cost.

In order to achieve the above object, an LCD touch device is provided, which has at least one liquid crystal display unit cell and a control unit, each of the liquid crystal display unit cells having: a first polarizing layer; a first transparent material layer, Located above the first polarizing layer; a first electrode above the first transparent material layer; a liquid crystal material layer above the first electrode; a second electrode above the liquid crystal material layer; a second a layer of transparent material over the second electrode; and a second polarizing layer over the second layer of transparent material; wherein the control unit is configured to be in the at least one of the liquid crystal display cells Applying a composite voltage source between an electrode and the second electrode to provide a display function and/or a a touch sensing function, wherein the composite voltage source has a DC voltage component and an AC voltage component, and the DC voltage component is used to control a liquid crystal alignment direction of the liquid crystal material layer to implement the display function. The AC voltage component is used as a touch signal. The control unit detects a touch event according to a parameter change of the touch signal to implement the touch sensing function.

In one embodiment, the first layer of transparent material is comprised of a material selected from the group consisting of glass, polyethylene terephthalate, and glass epoxy.

In one embodiment, the second layer of transparent material is comprised of a material selected from the group consisting of glass and polyethylene terephthalate.

In one embodiment, the first electrode is a transparent electrode.

In an embodiment, the second electrode is a transparent electrode.

In one embodiment, one of the planes above the second polarizing layer is used to provide a touch plane.

In an embodiment, one of the planes below the first polarizing layer is used to provide another touch plane.

In one embodiment, the parameter change amount is a change amount selected by a group consisting of an amplitude change amount, a phase change amount, and a frequency change amount.

In an embodiment, the touch sensing function is a self-capacitive touch sensing function.

In an embodiment, when the control unit operates in a first working mode, the control unit simultaneously provides the display function and the touch sensing function.

In an embodiment, when the control unit operates in a second mode of operation, the The control unit only provides the touch sensing function described.

In an embodiment, when the control unit is operating in a third mode of operation, the control unit provides only the display function.

In an embodiment, when the control unit operates in a fourth working mode, the control unit turns off the touch sensing function and the display function.

In one embodiment, each of the liquid crystal display cells further has a reflective layer underlying the first polarizing layer.

In one embodiment, each of the liquid crystal display cells further has a color filter layer between the first transparent material layer and the first electrode.

In one embodiment, the at least one liquid crystal display unit cell is used to form an LCD array, and the control unit has a scanning unit to drive the LCD array.

The detailed description of the drawings and the preferred embodiments are set forth in the accompanying drawings.

100, 300, 501-507‧‧‧ liquid crystal display unit

101‧‧‧reflective layer

102, 302‧‧‧ first polarizing layer

103, 303‧‧‧ first transparent material layer

104, 305‧‧‧ first electrode

105, 306‧‧‧ liquid crystal material layer

106, 307‧‧‧ second electrode

107, 308‧‧‧ second transparent material layer

108, 309‧‧‧Second polarizing layer

200, 400‧‧‧ control unit

201‧‧‧Composite voltage generating unit

202‧‧‧Touch detection unit

304‧‧‧Color filter layer

401‧‧‧Composite voltage generation and touch detection unit

402‧‧‧Scan unit

403‧‧‧Operation Control Unit

404‧‧‧Communication interface

410‧‧‧Information processing device

500‧‧‧LCD

FIG. 1a is a schematic diagram of driving a second electrode of a liquid crystal display cell with a composite voltage source for touch detection.

Figure 1b is an illustration of a waveform of one of the composite voltage sources of Figure 1a.

2a is a schematic diagram of an embodiment of an LCD touch device according to the present invention.

2b is a schematic diagram of another embodiment of an LCD touch device according to the present invention.

3 is a schematic diagram of still another embodiment of an LCD touch device according to the present invention.

The principle of the present invention will be described below. Please refer to FIG. 1a , which is a schematic diagram of driving a second electrode of a liquid crystal display cell with a composite voltage source for touch detection. In FIG. 1a, a voltage source V _S is a composite voltage source formed by a combination of a DC voltage and an AC voltage. An exemplary waveform is shown in FIG. 1b, which has a _DC voltage V _DC and an AC voltage V _{AC .} (Although the AC voltage V _AC in Figure 1b is presented as a square wave, it can also be a sine wave or other AC waveform). The DC voltage V _DC is used to control the liquid crystal alignment direction of one of the liquid crystal display cells to provide a display state, and the AC voltage V _AC is used for touch detection.

Since the driving voltage of the gate voltage is greater than a reaction time to be rotated by the liquid crystal molecules, the peak-to-peak value of the AC voltage V _AC is less than the threshold voltage, or the half cycle of the AC voltage V _AC is less than The AC voltage V _AC does not significantly affect the display state of the liquid crystal display unit cell during the reaction time. Therefore, when a finger approaches the liquid crystal display unit to derive an equivalent capacitance C _F , a parameter change amount generated by the AC component of the liquid crystal display cell across the voltage V _D can be used to perform a touch detection. The function, wherein the parameter change amount may be an amplitude change amount, a phase change amount, or a frequency change amount, and the touch detection function is a self-capacitance touch sensing function. Since the self-capacitive touch sensing function is widely known, it is not described herein.

In addition, the liquid crystal display unit cell can have multiple operating modes by enabling/disabling the DC component and the AC component of the composite voltage source, wherein when the liquid crystal display unit operates in a first operating mode, The DC component and the AC component of the composite voltage source are both enabled, so that the liquid crystal display unit simultaneously provides a display function and the touch sensing function; when the liquid crystal display unit operates in a second working mode The DC component of the composite voltage source is disabled and the AC component is enabled, so that the liquid crystal display unit only provides the touch sensing function; when the liquid When the crystal display unit operates in a third mode of operation, the DC component of the composite voltage source is enabled and the AC component is disabled, such that the liquid crystal display unit provides only the display function; and when the liquid crystal display When the unit cell operates in a fourth mode of operation, both the DC component and the AC component of the composite voltage source are disabled, and the touch sensing function and the display function are both turned off.

According to the above principle, the present invention provides an LCD touch device. Please refer to FIG. 2a , which is a schematic diagram of an embodiment of an LCD touch device according to the present invention. As shown in FIG. 2a, the LCD touch device has at least one liquid crystal display unit cell 100 and a control unit 200, wherein each liquid crystal display unit cell 100 has a reflective layer 101, a first polarizing layer 102, and a first transparent material. a layer 103, a first electrode 104, a liquid crystal material layer 105, a second electrode 106, a second transparent material layer 107, and a second polarizing layer 108; and the control unit 200 has a composite voltage generating unit 201 and a Touch detection unit 202.

The reflective layer 101, which may be made of aluminum, is used to reflect incident light of the liquid crystal display unit cell 100.

The polarization directions of the first polarizing layer 102 and the second polarizing layer 108 are perpendicular to each other.

The first transparent material layer 103 may be composed of glass, polyethylene-terephthalate, or glass epoxy resin.

The first electrode 104 is located above the first transparent material layer 103 and is a transparent electrode made of ITO (Indium Tin Oxide).

The liquid crystal material layer 105 is located above the first electrode 104.

The second electrode 106, located above the liquid crystal material layer 105, is a transparent electrode and may be composed of ITO.

a second transparent material layer 107, located above the second electrode 106, is made of glass or poly Composition of ethylene terephthalate.

The composite voltage generating unit 201 of the control unit 200 is configured to apply a composite voltage source V _C between the first electrode 104 and the second electrode 106 of the liquid crystal display unit 100 to provide a display function and/or a touch. a sensing function, wherein the composite voltage source V _C has a DC voltage component and an AC voltage component for controlling a liquid crystal alignment direction of the liquid crystal material layer 105 to achieve the display function, and the AC voltage The component is used as a touch signal. The touch detection unit 202 of the control unit 200 detects a touch event according to a parameter change of the touch signal to implement the touch sensing function. The touch sensing function is a self-capacitive touch sensing function, and the parameter change amount may be an amplitude change amount, a phase change amount, or a frequency change amount. In addition, the composite voltage generating unit 201 can combine a direct current voltage source and an alternating voltage source to generate a composite voltage source V _C using an active circuit (including a transistor or an amplifier) or a passive circuit, wherein the DC voltage source Both AC voltage sources can be enabled or disabled.

In the LCD touch device, a plane above the second polarizing layer 108 is used to provide a touch plane.

The control unit 200 has a plurality of working modes. When the control unit 200 operates in a first working mode, the composite voltage generating unit 201 outputs a composite voltage source V _{C having} a DC component and an AC component, and the touch detection is performed. The unit 202 detects the alternating component of the composite voltage source V _C to simultaneously provide the display function and the touch sensing function; when the control unit 200 operates in a second operating mode, the composite voltage is generated. The unit 201 outputs a composite voltage source V _{C having} only one AC component, so that the control unit 200 only provides the touch sensing function; when the control unit 200 operates in a third working mode, the composite voltage generating unit 201 Outputting the composite voltage source V _C having only the DC component, so that the control unit 200 only provides the display function; when the control unit 200 operates in a fourth operation mode, the composite voltage generating unit 201 turns off the composite voltage source V _C To turn off the touch sensing function and the display function. In addition, the control unit 200 can further have a communication interface to exchange data with an information processing unit.

Please refer to FIG. 2b , which is a schematic diagram of another embodiment of the LCD touch device of the present invention. As shown in FIG. 2b, the LCD touch device has at least one liquid crystal display cell 300 and a control unit 200, wherein each STN liquid crystal display unit cell 300 has a first polarizing layer 302, a first transparent material layer 303, and a a color filter layer 304, a first electrode 305, a liquid crystal material layer 306, a second electrode 307, a second transparent material layer 308, and a second polarizing layer 309; and the control unit 200 has a composite voltage generating unit 201 and a touch detection unit 202.

The polarization directions of the first polarizing layer 302 and the second polarizing layer 309 are perpendicular to each other.

The first transparent material layer 303 may be composed of glass, polyethylene-terephthalate, or glass epoxy resin.

A color filter layer 304 is disposed above the first transparent material layer 303 to provide a color filter function.

The first electrode 305 is located above the color filter layer 304 and is a transparent electrode made of ITO (Indium Tin Oxide).

The liquid crystal material layer 306 is located above the first electrode 305.

The second electrode 307, located above the liquid crystal material layer 306, is a transparent electrode and may be composed of ITO.

The second transparent material layer 308 is located above the second electrode 307 and is composed of glass or polyethylene terephthalate.

The composite voltage generating unit 201 of the control unit 200 is configured to apply a composite voltage source V _C between the first electrode 305 and the second electrode 307 of the liquid crystal display unit 300 to provide a display function and/or a touch. a sensing function, wherein the composite voltage source V _C has a DC voltage component and an AC voltage component for controlling a liquid crystal alignment direction of the liquid crystal material layer 306 to achieve the display function, and the AC voltage The component is used as a touch signal. The touch detection unit 202 of the control unit 200 detects a touch event according to a parameter change of the touch signal to implement the touch sensing function. The touch sensing function is a self-capacitive touch sensing function, and the parameter change amount may be an amplitude change amount, a phase change amount, or a frequency change amount. In addition, the composite voltage generating unit 201 can combine a direct current voltage source and an alternating voltage source to generate a composite voltage source V _C using an active circuit (including a transistor or an amplifier) or a passive circuit, wherein the DC voltage source Both AC voltage sources can be enabled or disabled.

In the LCD touch device, a plane above the second polarizing layer 309 is used to provide a touch plane; and a plane below the first polarizing layer 302 is used to provide another touch plane.

The control unit 200 has a plurality of working modes. When the control unit 200 operates in a first working mode, the composite voltage generating unit 201 outputs a composite voltage source V _{C having} a DC component and an AC component, and the touch detection is performed. The unit 202 detects the alternating component of the composite voltage source V _C to simultaneously provide the display function and the touch sensing function; when the control unit 200 operates in a second operating mode, the composite voltage is generated. The unit 201 outputs a composite voltage source V _{C having} only one AC component, so that the control unit 200 only provides the touch sensing function; when the control unit 200 operates in a third working mode, the composite voltage generating unit 201 Outputting the composite voltage source V _C having only the DC component, so that the control unit 200 only provides the display function; when the control unit 200 operates in a fourth operation mode, the composite voltage generating unit 201 turns off the composite voltage source V _C To turn off the touch sensing function and the display function. In addition, the control unit 200 can further have a communication interface to exchange data with an information processing unit.

Please refer to FIG. 3, which is a block diagram of still another embodiment of the LCD touch device of the present invention. As shown in FIG. 3, the LCD touch device has an LCD 500 and a control unit 400.

The LCD 500 is composed of a liquid crystal display unit cell 501-507 which constitutes a seven-segment display unit, wherein the liquid crystal display unit cells 501-507 can have the same structure as the liquid crystal display unit cell 100 of FIG. 2a or the liquid crystal display unit cell 300 of FIG. 2b. .

The control unit 400 has a composite voltage generating and touch detecting unit 401, a scanning unit 402, an operation control unit 403, and a communication interface 404.

The composite voltage generating and touch detecting unit 401 is configured to generate a composite voltage source V _C and provide a touch sensing function, wherein the composite voltage source V _C has a DC voltage component and an AC voltage component, and the DC voltage component It is used to control the liquid crystal alignment direction of one of the liquid crystal display cells 501-507, and the AC voltage component is used as a touch signal. The composite voltage generation and touch detection unit 401 detects a touch event according to a parameter change of the touch signal to implement the touch sensing function, wherein the touch sensing function is A self-capacitive touch sensing function, and the parameter variation amount may be an amplitude change amount, a phase change amount, or a frequency change amount.

The scanning unit 402 causes the composite voltage source V _{C to} sequentially drive the liquid crystal display cells 501-507 according to the control of a scan control signal S _SCAN .

The operation control unit 403 can generate the scan control signal S _SCAN to control the operation of the scan unit 402, and can also interact with the composite voltage generation and touch detection unit 401 and exchange data through the communication interface 404 and an information processing device 410. The information may be seven pieces of display data and/or touch detection data, and the information processing device 410 may execute a corresponding program according to the touch detection data.

As can be seen from the above description, the present invention has the following advantages due to its novel design:

1. The LCD touch device of the present invention can provide a display function and/or a touch sensing function by applying a composite voltage source to an LCD structure.

2. The LCD touch device of the present invention can provide a touch plane using an upper surface of an LCD structure.

3. The LCD touch device of the present invention can provide another touch plane using one of the lower surfaces of an LCD structure.

4. The LCD touch device of the present invention can detect a touch event by sensing an amplitude change, a phase change amount, or a frequency change amount of an alternating voltage of a composite voltage source.

5. The LCD touch device of the present invention can provide four modes of operation by turning off/on a DC voltage component and/or an AC voltage component of a composite voltage source.

6. The LCD touch device of the present invention can simplify the structure of the touch device to reduce product thickness, improve yield, and reduce cost.

The disclosure of the present invention is a preferred embodiment. Any change or modification of the present invention originating from the technical idea of the present invention and being easily inferred by those skilled in the art will not deviate from the scope of patent rights of the present invention.

In summary, this case, regardless of its purpose, means and efficacy, is showing its technical characteristics that are different from the conventional ones, and its first invention is practical and practical, and it is also in compliance with the patent requirements of the invention. Pray for the patents at an early date.

100‧‧‧LCD unit cell

101‧‧‧reflective layer

102‧‧‧First polarizing layer

103‧‧‧First transparent material layer

104‧‧‧First electrode

105‧‧‧Liquid material layer

106‧‧‧second electrode

107‧‧‧Second layer of transparent material

108‧‧‧Second polarizing layer

200‧‧‧Control unit

201‧‧‧Composite voltage generating unit

202‧‧‧Touch detection unit

Claims (16)

An LCD touch device having at least one liquid crystal display unit and a control unit, each of the liquid crystal display unit cells having: a first polarizing layer; a first transparent material layer located above the first polarizing layer; a first electrode located above the first transparent material layer; a liquid crystal material layer above the first electrode; a second electrode above the liquid crystal material layer; and a second transparent material layer located at the first Above the two electrodes; and a second polarizing layer above the second transparent material layer; wherein the control unit is configured to be used in the first electrode and the second electrode of the at least one liquid crystal display unit cell Applying a composite voltage source to provide a display function and/or a touch sensing function, wherein the composite voltage source has a DC voltage component and an AC voltage component for controlling the liquid crystal material One of the layers is arranged in a liquid crystal to achieve the display function, and the AC voltage component is used as a touch signal, wherein the control unit varies according to one of the touch signals. Detecting a touch event to implement the touch sensing function, and the peak-to-peak value of the AC voltage component is less than a liquid crystal rotation threshold voltage of the liquid crystal material layer, or a half cycle of the AC voltage component is smaller than the liquid crystal material One of the layers of reaction time. The LCD touch device of claim 1, wherein the first transparent material layer is selected from the group consisting of glass, polyethylene terephthalate, and glass epoxy. a material composition. The LCD touch device of claim 1, wherein the second transparent The material layer is composed of a material selected from the group consisting of glass and polyethylene terephthalate. The LCD touch device of claim 1, wherein the first electrode is a transparent electrode. The LCD touch device of claim 1, wherein the second electrode is a transparent electrode. The LCD touch device of claim 1, wherein a plane above the second polarizing layer is used to provide a touch plane. The LCD touch device of claim 6, wherein one of the planes below the first polarizing layer is used to provide another touch plane. The LCD touch device of claim 1, wherein the parameter change amount is a change amount selected by a group consisting of an amplitude change amount, a phase change amount, and a frequency change amount. The LCD touch device of claim 1, wherein the touch sensing function is a self-capacitive touch sensing function. The LCD touch device of claim 1, wherein the control unit simultaneously provides the display function and the touch sensing function when the control unit operates in a first working mode. The LCD touch device of claim 1, wherein the control unit only provides the touch sensing function when the control unit operates in a second mode of operation. The LCD touch device of claim 1, wherein the control unit provides only the display function when the control unit operates in a third mode of operation. The LCD touch device of claim 1, wherein the control unit turns off the touch sensing function and the display function when the control unit operates in a fourth working mode. The LCD touch device of claim 1, wherein each of the liquid crystal display cells further has a reflective layer under the first polarizing layer. The LCD touch device of claim 1, wherein each of the liquid crystal display cells further has a color filter layer between the first transparent material layer and the first electrode. The LCD touch device of claim 1, wherein the at least one liquid crystal display unit is used to form an LCD array, and the control unit has a scanning unit to drive the LCD array.